The output area and the lifetime of the electric motor are determined in particular according to the component temperatures reached during operation, above all the integrated motor electronics, the electrical output component, the bearings, and the motor drive components.
It is known from the state of the art that for improved output exploitation and lengthening of the lifetime of the motor, including its motor winding, ball bearing systems, and electronic components, active cooling should be provided onto the motor electronics. This is achieved in particular by implementing a cooling wheel, which sends a cooling air stream over the components to be cooled and thereby leads away the heat. Improved cooling of the components of the electric motor that are sensitive to temperature permit increased output performance at given surround temperatures and longer use of the motor at higher surround temperatures.
For example, DE 10 2012 107 109 A1 reveals a corresponding cooling design for an external rotor motor, in which a cooling stream is pushed actively over the electronics housing and over parts of the stator housing. The described solution in practice functions very well; however, it is not transferable to all types of electric motors, and in particular is not usable if the electronics housing is used axially separated from the stator housing.